From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Steigerwald Subject: 3.2-rc4: scrubbing locks up the kernel, then hung tasks on boot Date: Sat, 17 Dec 2011 18:33:34 +0100 Message-ID: <201112171833.34720.Martin@lichtvoll.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 To: linux-btrfs@vger.kernel.org Return-path: List-ID: Hi! =46inally I tried scrubbing the / BTRFS filesystem mentioned in the thr= ead=20 "speeding up slow btrfs filesystem". However the machine looks up hard=20 then. It repeats the last few seconds of audio all over again, no mouse= =20 and no ssh connection anymore: deepdance:~> btrfs scrub start /=20 scrub started on /, fsid [=E2=80=A6] (pid=3D5737) deepdance:~> Write failed: Broken pipe After the second attempt of doing this the machine stops on booting aft= er=20 the space cache enabled message. Then I get backtraced of hung tasks: http://martin-steigerwald.de/tmp/btrfs/2011-17-12-deepdance-hang-at-boo= t/ I am able to mount the filesystem from grml 2011.12-rc1 with 3.1 kernel= : root@grml ~ # Start lvm2 Setting up LVM Volume Groups Reading all physical volumes. This may t= ake=20 a while... Found volume group "deepdance" using metadata type lvm2 3 logical volume(s) in volume group "deepdance" now active =2E root@grml ~ # mount /mnt/debian root@grml ~ # mount /mnt/home root@grml ~ # dmesg | tail [ 55.479303] Installing knfsd (copyright (C) 1996 okir@monad.swb.de). [ 64.352088] eth0: no IPv6 routers present [ 75.744318] fuse init (API version 7.17) [ 75.801245] ipmi message handler version 39.2 [ 90.213880] end_request: I/O error, dev fd0, sector 0 [ 229.117153] Btrfs loaded [ 229.117962] device label debian devid 1 transid 201769=20 /dev/mapper/deepdance-debian [ 229.577244] btrfs: disk space caching is enabled [ 245.375875] device label home devid 1 transid 72021=20 /dev/mapper/deepdance-home [ 245.433137] btrfs: disk space caching is enabled root@grml ~ # umount /mnt/{debian,home} root@grml ~ # cat /proc/version Linux version 3.1.0-2-grml-486 (Debian 3.1.0-2+grml.3) (ch@grml.org) (g= cc=20 version 4.6.2 (Debian 4.6.2-5) ) #1 Fri Dec 9 00:25:07 UTC 2011 But after that 3.2-rc4 still doesn=C2=B4t boot. I am now trying to install a 3.1.0 debian kernel via chroot. Ok, after installing the 3.1.0 kernel it seems to work with 3.2.0-rc4 a= s=20 well again. Its again converting the old style inodes. Thus I think on = a=20 sudden crash there may be an issue with the inode cache in 3.2-rc4 that= =20 switching to 3.1.0, writing something, and then back to 3.2.0-rc4 works= =20 around. But then I had this after upgrading from 3.0 to 3.2-rc4 as well. I didn= =C2=B4t=20 report it here cause I thought it was a one-time issue. Hopefully you can make something out of the backtraces I tried to snaps= hot=20 with my digicam. Should I be concerned about the state of the filesystem? I will not try scrubbing it again for now ;) BTW the performance of the BTRFS fs while updating the inode cache is=20 abysmal. The machine is trying to boot for about 5 minutes now and stil= l=20 no KDM to see. Hmm, at least there is an SSH now. No nothing about thes= e=20 hard lock ups in syslog as I have suspected. Thanks, --=20 Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html